When connecting elements to form a structure, typical design efforts concentrate on the geometry of the interface and the static stiffness of the resulting connection. These design efforts attempt to match the complementary surfaces of each connecting element as closely as possible, and to provide the smoothest connection surfaces possible. Attempting to produce elements with these qualities requires strict tolerances and precise machining. Thus, such efforts are labor intensive, time consuming, and involve sophisticated machinery. Moreover, connections formed in this manner, while generally stiff and dimensionally accurate, have little or no damping.
The machining performance of a tool typically is a function of the dynamic stiffness of its structure. Dynamic stiffness is a measure of both the static stiffness of a connection, and the damping of the connection. Thus, while a connection may have increased static stiffness, the machining performance of a connection formed with little or no damping suffers.
Damping of a structure is commonly accomplished through the use of tuned mass dampers, increased numbers of connection interfaces, loosening of existing joints, or placement of shock absorbing materials between elements, each of which adds expense or complexity, as well as decreasing the static stiffness of the affected connections. Thus, what is needed is a statically stiff connection that has improved damping.